You may choose to challenge a gym as long as the owner is online and approves. You must defeat the 8 gyms before consulting the elite 4. Each gym can only be challenged once every 12 w/ the acception of the gym leader(ex: If the leader approves an early rematch):
Gyms(In Order):
1. jnoob- Flying
2.draquaza-Steel
3.Pokefan-Fire
4.xFreshgameRx-Dragon
5.KittyHawk-Water
6.Darkmoon-Ghost
7.Totorolove-Dark
8.mantrix-Normal
Once you have defeated all 8 gyms in order you may move on to challenge the elite 4 and the champion. The elite 4 may be challenged in any order you choose. You cannot switch pokes during this time unless you have lost:
1.SrExplosivo-Psychic
2.Avalugg-Fighting
3.PureChaos-Ice
4.Amitrik(Andre)-Electric
Once you have made your way through the elite 4, then you may challenge the champion. Again, you may not change up your team unless you've lost:
Champion: MaxPoison